Institute for Sustainable Agriculture, Spanish National Research Council (CSIC) , Córdoba , Spain.
Plant Signal Behav. 2019;14(10):e1651183. doi: 10.1080/15592324.2019.1651183. Epub 2019 Aug 5.
Salicylic acid (SA) is involved in several plant processes including responses to abiotic stresses. Although SA is thought to interact with other regulatory molecules in a complex way, currently, little information is available regarding its molecular mechanisms of action in response to abiotic stresses. In a previous work, we observed that drought-resistant oat plants significantly increased their SA levels as compared with a susceptible cultivar. Furthermore, exogenous SA treatment alleviated drought symptoms. Here, we investigated the interaction between SA and polyamine biosynthesis during drought responses in oat and revealed that SA regulated polyamine biosynthesis through changes in polyamine gene expression. Overall, SA treatment decreased the levels of putrescine under drought conditions while increased those of spermine. This correlates with the downregulation of the ADC gene and upregulation of the AdoMetDC gene. Based on the presented results, we propose that SA modulates drought responses in oat by regulating polyamine content and biosynthesis.
水杨酸（SA）参与了包括对非生物胁迫响应在内的几种植物过程。虽然 SA 被认为以复杂的方式与其他调节分子相互作用，但目前关于其应对非生物胁迫的分子作用机制的信息还很有限。在之前的一项研究中，我们观察到抗旱燕麦植株的 SA 水平明显高于易感品种。此外，外源 SA 处理缓解了干旱症状。在这里，我们研究了 SA 与多胺生物合成在燕麦干旱响应中的相互作用，揭示了 SA 通过改变多胺基因表达来调节多胺生物合成。总的来说，SA 处理在干旱条件下降低了腐胺的水平，同时增加了亚精胺的水平。这与 ADC 基因的下调和 AdoMetDC 基因的上调有关。根据提出的结果，我们提出 SA 通过调节多胺含量和生物合成来调节燕麦对干旱的响应。
